Automatic belt training troughing roller assembly



April 17, 1962 R. F. LO PRESTI 3,029,928

AUTOMATIC BELT TRAINING TROUGHING ROLLER ASSEMBLY Filed March 21, 1958 2 Sheets-Sheet 1 IN V EN TOR.

I Roy F LoPresci W I 4% A TrOR/yE Y April 17, 1962 R. F. LO PRESTI 3,029,928

AUTOMATIC BELT TRAINING TROUGHING ROLLER ASSEMBLY Filed March 21, 1958 2 Sheets-Sheet 2 BELT 01v CENTER IN VEN TOR.

BY Roy F LoPresti 47 M 4 M ATTORNEY United States atent p 3,029,928 AUTOMATIC BELT TRAINING TROUGHING ROLLER ASSEMBLY Roy F. Lo Presti, Chicago, 11]., assignor to Goodman Manufacturing Company, Chicago, 111., a corporation of Illinois Filed Mar. 21, 1958, Ser. No. 723,625 2 Claims. (Cl. 198-192) This invention relates generally to troughing idler assemblies for belt conveyors, and more particularly to an improved automatic belt training troughing idler assembly for use in a rope or flexible strand sideframe conveyor of the general type which is illustrated in Craggs et al. Patent No. 2,773,257.

This application is a continuation in-part of LoPresti application Serial No. 523,454, filed July 21, 1955, now abandoned. g

.An important but not generally known characteristic of troughing idler assemblies of the type having a center roller flanked bya pair of upwardly inclined wing rollers is that the center roller has a far greater effect on training of the belt than the wing rollers. As a resultof this, one of the wing rollers may be oriented to tend to detrain the belt but if the center roller is oriented in the proper direcor movable; that is, so the interconnections can shift horizontally forward or backward incidental to the steering or training function, and so these interconnections can shift up and down in connection with the impact absorbing function. And the bracket connections at the ends of the Wing rollers will be flexible to permit swinging or swivelling of the wing rollers at least in a horizontal tion to train the belt, then the belt will stay in train, that t is it will run properly centered. As a result, the center roller is aptly regarded as the training roller and if a troughing idler assembly is capable of turning the training roller to a position to urge an off-center belt back toward center, in response to the off-center condition of the belt, then the assembly is automatically self-centering or self-training.

One way of providing a self-training roller which is conventional is to mount the entire troughing assembly including the training roller and the wing rollers for turning movement about some vertical axis, or axes, so the entire assembly turns, in a horizontal plane, in .a direction to urge the off-center belt back toward center.

By the present invention, it has been found unnecessary to shift the entire troughing idler assembly to carry out the corrections needed to maintain the belt on center. I have found the belt can be maintained centered merely by turning the training roller in the proper corrective direction, even though one of the wing rollers itself may be disposed in a direction which apparently would tend to de-train an otf-center belt even farther.

Accordingly, it is a specific object of the present invention, when applied to the type of troughing idler assembly having a center training roller flanked by a pair of wing rollers, to provide interconnections between the rollers and to provide connections between the end rollers and suitable mounting brackets so the rollers can swivel or flex about said interconnections and connections whereby one or both wing rollers will swivel in response to movement thereacross of an off-center belt, the wing rollers swivelling in the direction to turn the training roller in the proper direction to re-train the belt. In brief, the present invention contemplates selectively turning the training roller in the proper corrective direction, irrespective of whatever position may be assumed by the wing rollers.

Another object is to apply the above-mentioned training or steering principle to a troughing idler assembly which can be employed on a flexible strand sideframe conveyor in which the roller assembly is required to flex up and down bodily in absorbing impact loads.

, The construction which has been developed in accordance with the present invention to carry out the above objects involves providing interconnections between the :11 and 12, the strands being spanned by an automatic belt training troughing idler assembly indicated generally rollers which are universally flexible, pivotal, swivellable, I

direction incidental to the steering function.

Yet another object is to provide a troughing idler assembly having idler rollers mounted upon non-rotatable shafts which are interconnected for free articulating movement in both horizontal and vertical direction, each end shaft of the assembly being connected to a bracket adapted to be supported upon a flexible support strand to provide swinging movement of the end shaft in a horizontal direction relative to the bracket and to further provide movement of the end shaft in a vertical direction with the strand.

Other objects and important features of the invention will be apparent from a study of the specification following taken with the drawings which together show a number of preferred embodiments of the invention and what are now considered to be the best modes of practicing the principles thereof. Other embodiments of the invention maybe suggested to those having the benefit of the teachings herein, and the scope of the invention is therefore intended not to be limited by the precise embodiments herein shown, such other embodiments being intended to be reserved especially as they fall within the scope and purview of the subjoined claims.

In the drawings:

P16. 1 is a perspective .view of an endless conveyor having an improved troughing idler assembly according to the present invention embodied therein;

FIG. 2 is an elevation view of one of the troughing idler assemblies seen in FIG. 1, said view being taken in the direction of the arrows 2-2 of FIG. 1;

FlG. 3 is a view similar to FIG. 2, but to an enlarged scale, showing an alternate form of swivel connection for the troughing rollers of the troughing idler assembly;

FIG. 4 is a view similar to FIG. 2 showing an alternate form of connection of the troughing rollers to a support bracket;

FIG. 5 is a reduced in scale elevation view showing the normal contour adopted by the troughing idler assembly when the conveying reach runs on center;

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a view similar to FIG. 5 showing the contour adopted by the troughing idler assembly when the conveying reach runs oil-center;

FIG. 8 is a plan view thereof, showing the positions adopted by the rollers during such off-center loading;

FIG. 9 is an elevation view of another embodiment of the invention where the end of a wing roller of the troughing idler assembly is arranged to have horizontal swiveling movement with respect to a support bracket which in turn has vertical movement by reason of the torsional and translational deflections of the support strand; and

FIG. 10 is a plan view thereof.

Referring now to FIG. 1 of the drawings, there is shown a belt conveyor indicated generally by the reference numeral 10. Said conveyor is of the type which is supported upon a pair of laterally spaced flexible strands by the reference numeral 15, said assemblies being spaced at intervals throughout the length of the flexible strands 11 and 12.

The troughing idler assembles 15 are arranged to support the conveying reach of an endless belt 14, in such a fashion as to provide the proper troughing contour thereto both during its unloaded condition and during the loaded condition thereof. The endless belt seen in FIG. 1 has a return reach, not shown.

Referring now to FIG. 2 of the drawings, the troughing idler assembly 15 consists of a troughing roller assembly including an intermediate roller assembly, here a central load supporting or training roller 16, which is'flanked by inclined wing rollers 17 and 18. A swiveling interconnection is afforded between the rollers 16 and 17 and an identical interconnection is afiorded between rollers 16 and 18.

Each of the rollers is of a unitary construction and is mounted to turn upon a dead shaft 19, which is longer than the roller. Rollers 16 and 17 are interconnected by means of bails or swivels 21 and 22, which are respectively pinned to the adjacent shafts 19 by pins 23 and 24. Rollers 16 and 18 are interconnected in the same fashion by means of a swivel 26 having a pin connection 27 to the shaft 19 of roller 16 and by means of a swivel 28 having a pin connection 29 to the shaft 19 of roller 18.

The assembly thus far described is arranged to be suspended from the flexible strands 11 and 12 by means of strand connectors, here U-shaped brackets 31, 31, each having a bight 32 frictionally engaging the strand 11 or 12 which is held in the bight by a drift pin 33 passing through openings 34 in the bracket.

Each of the U-shaped brackets 31 has an opening 36 therein arranged to receive a swivel 37 which has a pinned connection 38 to the end portion of the shaft 19 of one of the wing rollers 17 or 18.

The assembly thus far described is free to move both in vertical and horizontal directions. The entire assembly can displace vertically under load, and the strands 11 and 12 can move laterally toward each other so the load on the conveying reach 14 may be effectively pocketed. As will appear in more detail, the rollers are free to move horizontally to correct misalignment of the conveying reach 14.

Referring now to FIG. 3 of the drawings, there is shown another embodiment of the invention wherein the shafts 19 are interconnected by means of eye screws 39 tapped into the ends of the shafts. Each pair of eye screws forms an interconnection between adjacent shafts 19 so they, and the rollers journaled thereon, are free to move in both horizontal and vertical directions.

It may be noted that in both embodiments just described, the shafts 19 are dead shafts, and do not turn, the rollers 16, 17 and 18 turning thereon.

Referring now to FIG. 4, there is shown another embodiment where the outer end of the wing roller shaft 19 is provided with a hook 41 engaged within an opening 42 in one of the limbs of the bracket 31.

Referring now to FIGS. 9 and of the drawings, there is shown another embodiment of the invention where the interconnected rollers are free to move in both vertical and horizontal directions. In this embodiment, each end roller shaft 19 has a flexible, swiveling connection with the corresponding bracket which in turn is mounted on the flexible strand, the connection affording swiveling movement of the roller relative to the bracket in a generally horizontal direction only, the movement of the end roller in a vertical direction relative to the bracket being constrained by the torsional resistance of the flexible strand which is effective to aid in support of load on the belt.

In the FIGS. 9, 10 embodiment the rollers are shown interconnected in the same manner as seen in FIG. 3. The shafts 19 upon which the rollers turn are interconnected by eye screws 39. The outer ends of the shafts 19, that is, adjacent the flexible strands 11, 12, are each connected to a bracket 43 formed from a stamping bent upon itself to form a U-shaped stirrup 44 having an upper limbs 46 and a lower limb 47 embracing the shaft 19. A pin 48 passes through the limbs 46 and 47 and the shaft 19 to enable the wing roller 18 to have swiveling movement with respect to the bracket 43 in a horizontal direction.

The other end of the bracket 43 is bent in the shape of a hook 49 having an upper portion 51 and a lower portion 52 which straddles the strand 11 or 12. The upper and lower hook portions have aligned apertures 53 to receive the locking pin 33a which forces the strand 11 or 12 into a bight 54 connecting the upper and lower portions 51 and 52.

A feature of the FIGS. 9, 10 embodiment is that, while a wing roller 18 is free to swing generally horizontally about the pivot pin 48 incidental ot the steering function hereinafter referred to in describing FIG. 8, the connection between the wing roller and adjacent bracket 43 is rigid in a vertical plane transverse to the flexible strand. This prevents downward displacement of the wing roller relative to the bracket which, under an extremely heavy edge load might bring the projection of the upper wing roller surface into line with the locking pin 33a and cause the belt edge to tear against that pin when running otf center. By contrast, with the vertically rigid construction shown in FIGS. 9, 10, the belt can run off momentarily as shown in broken lines in FIG. 9 and positively remain clair, high above the pin 33a, regardless of the loading on the belt. Another advantage of the FIG. 9, 10 embodiment is that the entire portion of the roller assembly from the interconnection 39, 39 to the rope 11 or 12, is a relatively rigid cantilever member in a vertical direction, utilizing the torsional resistance of the rope to help support the belt. The specific bracket arrangement 43, which maintains the centerline of the wing roller shaft above the rope 11 or 12 is the subject of a copending application of Clarence H. Brown and John 8. Newton, Serial No. 681,946, filed September 4, 1957, now United States Patent No. 2,911,090.

It may be noted that in all of the assemblies shown the rollers 16, 17 and 18 have freely swivelable interconnections so they may adopt positions with reference to each other under conditions as will now be described. Likewise, all the wing rollers have connections with the corresponding brackets enabling the wing rollers to swing generally horizontally relative to the brackets.

By way of example and referring to FIGS. 5 and 6 where the action of the roller assembly 15 is illustrated, it adopts the position shown during a uniformly loaded condition of the conveying reach 14. Under such condition, the central or training roller 16 adopts a generally horizontal position as seen in FIG. 5, while the wing rollers 17 and 18 adopt the inclined positions shown. Since the rollers of the assembly 15 are swivelable, the load on the reach 14 is such as to displace the center load supporting roller 16 downstream as seen in FIG. 6, the wing rollers 17 and 18 also being swung downstream.

Thus, FIGS. 5 and 6 illustrate what may be regarded as a normal condition in which the belt runs properly in train along the center of the troughing roller assembly, the line of action of the training roller 16 being represented by the arrow A which is pointed down the middle of the belt in the direction of the longitudinal axis of belt travel.

Consider now the condition obtaining when the conveying reach 14 runs offcenter as shown in FIGS. 7 and 8 where it is shown running otfcenter to the left. In the plan view, FIG. 8, the direction of movement is from top to bottom of the page. The belt reach 14 will tend to drag the wing rollers forward in a degree which is more or less proportional to the amount of the wing roller engaged by the belt. Thus, in FIG. 8 it will be seen that more of Wing roller 17 than of the wing roller 18 is engaged by the belt and as a result it is canted forward to a greater degree. This cants the training roller 16 so that its line of action, represented by the arrow B, urges the belt back toward the center of the roller assembly. When centered, the stable condition of FIGS. 5, 6 is resumed. The steering etfect of the training roller on the belt is so pronounced that it actually causes the belt to climb up the roller assembly, as it will be seen by referring to FIG. 7 that rightwise movement of the belt involves climbing up both rollers 16 and 18. Further, by referring to FIG. 8, it will be noted that at least theoretically the wing roller 17 may even have some detraining influence on the belt. In practice, this has been found to be insignificant as the training influence of the canted center roller 16 far overrides it.

Another factor which favors the shifting of the training ro-ller in the corrective direction responsive to movement of an oficenter belt results from the peculiar orientation existing when a roller assembly which is non-symmetrically deflected downwardly is dragged forward by the belt. This can be seen clearly in FIGS. 7 and 8. When the belt is oflcenter, to the left, whether it is carrying material or not, it constitutes an oficenter load, which deflects the interconnection 21, 22 downwardly more than interconnection 26, 28; see FIG. 7. Since the interconnection 2.1, 22 is the low point, it will be swung farther forward than interconnection 26, 28 by the drag of the belt, which orients the training roller 15 in the pro-per belt correcting direction as shown in FIG. 8.

Thus, as demonstrated above, there are two important factors in the present invention, both contributing to the V shifting of the training roller in the proper corrective direction to steer an oficenter belt back to center. One is the efi'ect of ditferential drag on the Wing rollers. The other is the forward shifting of the low point (21, 22 in FIG. 7) by the belt drag.

While the invention has been described in terms of a number of preferred embodiments thereof its scope is intended to be limited only by the claims here appended.

I claim:

1. In combination, in a belt conveyor of the type in which the conveying reach of a conveyor belt is supported by idler assemblies and the return reach by return roller means,

a pair of flexible strands supported in co-planar relationship to one another along a conveying course,

a plurality of idler assemblies suspended from the flexible strands at intervals therealong, and

an endless load carrying conveyor belt supported by the idler assemblies, said idler assemblies including a troughing idler assembly having a pair of wing rollers,

each wing roller being shaft supported, said pair of wing rollers flanking an intermediate roller assembly, said intermediate roller assembly including at least one shaft supported belt training roller, and means for moving the inner ends of the wing rollers downstream in response to an oil? center condition of the conveyor belt into positions in which one of the wing rollers is moved into a belt training position and the other wing roller to a belt detraining position, the one roller exerting, in conjunction with the intermediate rollerfassembly, a preponderating training effect on the'belt, said means including load transmitting universal joints pivotally connecting the wing rollers and the intermediate roller assembly to one another in generally end to end relationship to thereby enable the rollers to flex, with respect to one another, in horizontal and vertical directions simultaneously so that a wing roller can be oriented in a belt detraining position while the intermediate roller assembly and the other wing roller are oriented in a belt training position,

and a strand connector assembly at each end of the troughing roller assembly connecting an end of the troughing roller assembly to an adjacent flexible strand, said strand connector assemblies enabling the first and second wing rollers to flex in a plane parallel to the plane of the conveyor belt passing there over.

2. The belt conveyor of claim 1 further characterized in that the strand connector assemblies at each end of the troughing roller assembly includes an elongated member pivotally connected at one of its end portions to the outer end of an adjacent roller shaft so as to enable the shaft and roller Supported thereby to pivot about an axis generally perpendicular to the plane of the conveyor belt, and secured at its other end portion to the flexible strand in such fashion that said elongated member is restrained from movement along or about the strand, said elongated member being bodily inflexible so as to restrain swinging movement of the outer end of the wing roller about the flexible strand in a vertical plane and thereby maintain the projection of the upper surface of each wing roller above the flexible strand under all conditions of load.

References Qited in the file of this patent UNITED STATES PATENTS 

